Abstract

GALLO-REYNOSO, Juan Pablo; MACIAS-SANCHEZ, Samuel; ARELLANO-NICOLAS, Edith  and  GONZALEZ-ROMERO, Alberto. Length, body mass, and growth of the neotropical otter (Lontra longicauidis annectens) in Mexico. Therya [online]. 2013, vol.4, n.2, pp.219-230. ISSN 2007-3364.  https://doi.org/10.12933/therya-13-132.

Neotropical otter is a medium to large size species, adult male has a mean size of 142 ± 11 cm (range: 130 - 162 cm, n = 9), with a mean body mass of 16 ± 5 kg (range: 10 - 24 kg, n = 9); adult female has a mean size of 116 ± 9 cm (range: 109-127 cm, n = 4) with a mean body mass of 13 ± 2 kg (range: 10-15 kg, n = 4). A growth curve was performed using data from size-body mass regarding the age of 24 individuals (some individuals were measured at different ages, thus the sample size might be larger at certain ages). The largest individual measured correspond to an adult male from Río Pinela, State of Guerrero, with a total size of 162 cm, and weight of 24 kg, very close to the reported size and weight for the giant otter (Pteronura brasiliensis) which is of 141 to 163 cm in length and 24 to 28.8 kg in weight. A significant length-body mass relationship was found (r² = 0.964; P < 0.001, n = 33). With this regression, body mass can be estimated with a given length and vice versa for Neotropical otters. Theoretical growth was developed for pups by each sex. The relationships found between size and age and between body mass and age, have the utility to predict body mass, size and approximate age of the pups that happen to be found abandoned, or of any other age class individual that are taken to a zoo for their care.

Keywords : Body mass; growth; Lontra longicaudis; Neotropical otter; size.